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Transcutaneous spinal cord stimulation combined with locomotor training to improve walking ability in people with chronic spinal cord injury: study protocol for an international multi-centred double-blinded randomised sham-controlled trial (eWALK)

Abstract

Study design

An international multi-centred, double-blinded, randomised sham-controlled trial (eWALK).

Objective

To determine the effect of 12 weeks of transcutaneous spinal stimulation (TSS) combined with locomotor training on walking ability in people with spinal cord injury (SCI).

Setting

Dedicated SCI research centres in Australia, Spain, USA and Scotland.

Methods

Fifty community-dwelling individuals with chronic SCI will be recruited. Participants will be eligible if they have bilateral motor levels between T1 and T11, a reproducible lower limb muscle contraction in at least one muscle group, and a Walking Index for SCI II (WISCI II) between 1 and 6. Eligible participants will be randomised to one of two groups, either the active stimulation group or the sham stimulation group. Participants allocated to the stimulation group will receive TSS combined with locomotor training for three 30-min sessions a week for 12 weeks. The locomotor sessions will include walking on a treadmill and overground. Participants allocated to the sham stimulation group will receive the same locomotor training combined with sham stimulation. The primary outcome will be walking ability with stimulation using the WISCI II. Secondary outcomes will record sensation, strength, spasticity, bowel function and quality of life.

Trial registration

ANZCTR.org.au identifier ACTRN12620001241921

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Fig. 1

Data availability

Data sharing is not applicable to this article as no datasets were generated or analysed. For the main trial, full de-identified data used to generate all results will be made available with the publication.

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Acknowledgements

The authors acknowledge Professor Rob Herbert/Peter Humburg for their statistical advice; SpinalCure Australia, Spinal Cord Injuries Australia and Paraquad for their assistance with an advertisement for this trial; and the support of local Spinal Cord Injury Units at each site.

Funding

Funding for this study has been received from SpinalCure Australia and Catwalk NZ.

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Contributions

Conceptualisation: EAB, MEH, CLB, BBL, EJM, JEB, and SCG; Methodology: EAB, MEH, CLB, BBL, EJM, JEB, and SCG; Writing—original draft: EAB, EJM, and MEH; Writing—review & editing: All authors; Project administration: EAB, MEH, CLB, BBL, EJM, JEB, and SCG; Funding acquisition: SG and JB.

Corresponding author

Correspondence to Simon C. Gandevia.

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Bye, E.A., Héroux, M.E., Boswell-Ruys, C.L. et al. Transcutaneous spinal cord stimulation combined with locomotor training to improve walking ability in people with chronic spinal cord injury: study protocol for an international multi-centred double-blinded randomised sham-controlled trial (eWALK). Spinal Cord 60, 491–497 (2022). https://doi.org/10.1038/s41393-021-00734-1

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